Nonaqueous G-Quadruplex Ionogels

Abstract

Supramolecular ionogels, as an emerging class of materials, utilize the intriguing properties of ionic liquids (ILs) and offer a promising method for constructing functional materials in anhydrous solvents. G-Quadruplex, assembled from guanine-rich nucleic acid building blocks, is an important structure closely associated with life and leads to the gelation for constructing versatile materials, such as the electrolytes of supercapacitors. Herein, we design and fabricate G-quadruplex ionogels using an unreported cation. Among the metal acetylacetonates under investigation, iron(III) acetylacetonate is distinctive in its capacity to stabilize G-quadruplexes through a reaction with the solvent ethylammonium nitrate (EAN), resulting in the formation of Fe(acac)²⁺. The ionogel displays high ionic conductivity (6.43 mS·cm^–1), a wide electrochemical stability window (2.86 V), and self-healing properties. The supercapacitor based on the G-quadruplex ionogel electrolyte delivers a gravimetric capacitance of 91.8 F·g^–1, a high energy density of 32.6 W h/kg, and a power density of 319.8 W/kg at a current density of 0.2A·g^–1. Therefore, the present findings have important implications for deepening the understanding of G-quadruplex structures and metal acetylacetonate complexes and provide an approach to fabricating ionogel electrolytes for high-performance supercapacitors.